Compared study of the early shock stage effects on whole body and intestinal epithelium was taken among radiation injury (12.16Gy irradiation of a ~(60)Co source), burns (5%, 10%, 15%, 25%TBSA Ⅲ?) and combined radiation-burn injury animals. Seven hundred and fifty mice were examined totally. The incidence of severe shock increased as the extent of burn area increased. The early burn shock was the most important cause of death in combined injury animals before 48h postinjury, and represented 8 special feature of combined effects. Early shock could be prevented and early stage death peak disappeared through fluid replacement to the combined injury animals, meanwhile, severe damage of intestinal epithelium resulted by the shock mitigated. Thus, if the shock was effectively treated, further treatment and regeneration of intestinal epithelium could become possible.

Objective To review the characteristics of human defensin 5 (HD 5), including molecular structure, antibacterial activity and gene expression, and to show its development prospect as a new drug in the treatment of enterogenic infection. Methods The published papers about HD 5 were reviewed to summarize its research progress. Results Being a 3-5 KDa cationic peptide rich in cysteine and arginine, especially without glycosylated side chain, HD 5 plays its antibacterial role against positive and negative Gram's bacterium, fungi, spirochete, protozoan and enveloped virus with the special active center composed of three disulfide bonds. HD 5 encoding gene alpha defensin 5 (DEFA 5) localizes at the 8th chromosome P21 pter with 449 bp, which includes five pieces of sequence: 5′ untranslated region (1-40),signal peptide (41-97), propiece (98-226), mature peptide (227-322),and Poly A (433-438).Conclusion As a broad spectrum and effective endogenous antimicrobial peptide, HD 5 would be a promising alternative peptide against enterogenic infection if the accessibility to its mass production is settled.

One hundred and forty mice, weighing 30-35 grams, were divided into irradiation group (12 Gy total body irradiation from a 60Co source), combined radiation-burn group (12 Gy total body irradiation and 15% TBSA third degree burns), and normal control group.The dynamic changes of the intestinal epithelium were observed with light and electron microscopes and autoradiography within 96 hours after injuries, and attention was paid to the formation and conversion of the misshapen cells. It was Jound that the proliferative cycle of the young cells in the intestinal crypts which were severely injuried by irradiation was significantly retarded, and their G1-phase to G2-phase were prolonged. These cells gradually changed into misshapen cells. Some of the misshapen cells could not divide and finally they wer.e desquamated; abortive proliferation was found in some of them; some others showed pathological karyokinesis. Thus polymorphic cells were formed. It was difficult to show that the misshapen cells could take part in the repair of the intestinal epithelium. It is speculated that the misshapen cells might to some extent have the function of absorption, secretion and barrier.

Objective To breed and identify steroid receptor coactivator-3 (SRC-3) knock-out mice. Methods Heterozygote mice were bred and reproduced. Wild genotype, heterozygote genotype, and homozygote genotype would appear in offsprings of parents. Genome DNA extracted from the murine tails was subjected to PCR for genotype identification. Male homozygote mice were selected to mate with the female heterozygote mice for acquiring homozygote baby mice according to Mendel law. Results Breeding and reproducing were successful and more heterozygote genotype mice were reproduced. Conclusion Appropriate methods for breeding, reproducing, and identifying are the effective way for acquiring SRC-3 knock-out mice from heterozygote mice.

Objective To construct a bait vector containing human glucocorticoid receptor(GR) ligand binding domain (LBD) in yeast two hybrid system in order to screen its cDNA library Methods PCR was used to amplify GR LBD fragment from the fetal liver cDNA library with the primers designed in accordance with the sequence in GenBank GR LBD The product was inserted into pGEM(r) T Vector Systems After verified with restriction endonuclease digestion of SmaⅠ/SalⅡ, the vector was inserted into the "bait plasmid" pGBKT7 (named as pGBKT7 GR LBD) After confirmation with restricted endonuclease digestion and sequence analysis, the plasmid was transformed into the yeast cell AH109, and the transformants were selected on SD/ Trp plates The interaction between GR and SRC 1 was tested by ? gal activity with yeast two hybrid system Results The amplified product of 893 bp was inserted into pGEM(r) T Vector and proven to be successful with double restriction enzyme digestion Sequence analysis revealed that the sequence was correctly inserted into pGBKT7 with a right reading frame AH109 [pGBKT7 GR LBD] grew on SD/ Trp plates, but not on the other selective media GR could interact with SRC 1 Conclusion The bait plasmid pGBKT7 GR LBD constructed expresses GR LBD correctly, and can't activate the transcription of reporter gene alone in yeast two hybrid system

Objective　To study the effect of glucagon-like peptide 2 (GLP-2) on mitogen-activated protein kinase (MAPK) activity in small intestinal epithelia in mice after radiation injury and its relation with the change of small intestinal epithelial proliferation. Methods　Mice were given a single dose of 8 Gy of total body 60Co gamma irradiation and then divided into GLP-2 and control groups. The activity of MAPK and proliferation rate in small intestinal epithelia were measured. Results　The activity of MAPK in small intestinal epithelia was higher in GLP-2-treated mice than in irradiated mice, and the proliferation rate in small intestinal epithelia significantly increased in GLP-2-treated mice. These two indices were of significantly positive correlated. Conclusion　GLP-2 can promote small intestinal epithelial proliferation in irradiated mice, and this may be related to activation of MAPK in small intestinal epithelia.

Objective　To investigate the effects of glucagon-like peptide 2 (GLP-2) on recovery of small intestinal epithelia from radiation injury in mice. Methods　Mice received a single 8 Gy dose of total body irradiation from 60Co gamma ray followed by treatment with GLP-2 or vehicle. DNA and protein content in small intestinal mucosa were measured, and small intestine was processed for histological examination with light microscope and scanning electron microscope. Results　Small intestinal mucosal DNA and protein content, villus height, and villus number significantly decreased in irradiated mice, partial villus tips were ulcerated. GLP-2 administration caused increase in DNA and protein content, villus height, and villus number as compared with irradiated control group. Meanwhile, the villus tips were lack of ulceration. Conclusion　GLP-2 can promote recovery of small intestinal epithelia from radiation injury in mice.

Objective To study the relationship of expression of central cortex glucocorticoid receptor (GR) at protein level with GR expression in the liver at protein level and with changes of serum cortisol and adrenocorticotropic hormone (ACTH) following severe closed traumatic brain injury (TBI) in mice. Methods Severe TBI was established in awake mice by using a BIM-Ⅲ biomechanical machine. At 0.5, 2, 8, 24, 48 and 72 hours after TBI, the total cytosolic GR in the cortex and liver were detected with Western blotting. Levels of serum ACTH and cortisol were measured by ELISA technique and radio-immunological assay (RIA) respectively. Results The expression of GR both in the cortex and liver were obviously down-regulated at protein levels at 2-72 hours after TBI and increased slowly eight hours after injury. The GR in the liver showed no recovery at 72 hours after injury and that in the cortex was decreased continually at 24 hours after injury. Serum ACTH and cortisol levels were increased markedly compared with control group, when there were two different peaks in the observation curve.Conclusion There is glucocorticoid resistance both in the central and peripheral tissues after severe closed TBI in the awake mice, which changes in a time-dependent manner.

Traumatic stress in the normal individual results in activation of the sympatho-adrenal system causing a rise in noradrenaline and adrenaline, acute phase response in liver ,and activation of the hypothalamic-pituitary-adrenocortical(HPA)system resulting in elevated levels of cortisol. Studies in animals and in humans with posttraumatic stress disorder indicate that successful adaptation to stress is a prerequisite for the survival of all organisms living in an enviroment in which noxious stimuli are constantly present.